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Re: Why does top capacitance work? (fwd)



---------- Forwarded message ----------
Date: Thu, 27 Feb 1997 19:14:15 -0800
From: Open Minded <unknown-at-apc-dot-net>
To: Tesla List <mod1-at-pupman-dot-com>
Subject: Re: Why does top capacitance work? (fwd)

Tesla List wrote:
> 
> ---------- Forwarded message ----------
> Date: Thu, 27 Feb 1997 00:48:41 +0000
> From: "John H. Couture" <couturejh-at-worldnet.att-dot-net>
> To: Tesla List <mod1-at-pupman-dot-com>
> Subject: Re: Why does top capacitance work? (fwd)
> 
> At 05:29 AM 2/26/97 +0000, you wrote:
> >
> >
> >---------- Forwarded message ----------
> >Date: Tue, 25 Feb 1997 20:20:30 -0800
> >From: Greg Leyh <lod-at-pacbell-dot-net>
> >To: Tesla List <mod1-at-pupman-dot-com>
> >Subject: Re: Why does top capacitance work? (fwd)
> >
> >Ed Sonderman wrote,
> >>
> >>
> >>  Ed,
> >>
> >>  I was curious if you noticed where the extra 3kVA power went when you
> >>  increased to 7kVA.  Did something get 3kVA hotter?
> >>
> >>  -GL
> >>   >>
> >> GL,
> >>
> >> I measure the power into the system by monitoring the pole pig primary
> >> current and voltage.  The only thing I can tell you for sure is the watts
> >> consumed.  As to where they went, I am not sure, maybe into the spark gaps?
> >>  Maybe it gets reflected back into the primary and is lost as radiated
> >> energy?
> >>
> >> Ed Sonderman
> >
> >
> >Ed,
> >
> >At this point, it seems crucial to know _how_ the extra power was applied to
> >the coil.  Did you increase the primary voltage (longer sparks), or increase
> >the gap rate (thicker, faster sparks above ~300 PPS) ??
> >
> >-GL
> >
> >------------------------------------------------
> 
> Ed & GL -
> 
> Finding the true wattage input to a Tesla coil is impossible without very
> elaborate instrumentation. The power is voltage times current times cosine
> of the power factor. The voltage is a rough sine wave but the current is in
> pulses of varying waveshapes. The power factor cannot be metered with
> standard meters because finding the power factor of pulses is a tricky
> problem. All standard AC meters are only for RMS voltages and currents. Non
> sinusoidal conditions require special instrumentation.
> 
> Adding power to a T.C. (usually by increasing the voltage) and getting very
> little increase in spark length would indicate that the extra current you
> are seeing is reactive and not doing much good. Also, the spark output of a
> Tesla coil is dependent on the energy input minus the losses. If the energy
> input is increased but the losses also increase due to higher voltages in
> the secondary there will be little increase in spark length. The overall
> design of the Tesla coil must be coordinated so losses are a minimum and
> spark length a maximum.
> 
> The problem with comparing the spark length of a classical Tesla coil vs the
> magnifier is in the difficulty of determining the true wattage inputs of the
> two systems.
> 
> Note that the top capacitance's primary function is to keep the Tesla coil
> in tune. It's next in importance function is to store electric charge. The
> size of this capacitance should be coordinated with the true wattage input
> to the Tesla coil system. Wattage input represents coulombs of electricity
> and the top capacitance stores coulombs as a function of capacitance and
> voltage.
> 
> I would be interested in hearing comments on how the true wattage input
> could be metered so we can compare the classical TC with the magnifier.
> 
> John Couture


John -

  What about the classic hot-wire ammeter of years gone by? You would
get a nicely averaged/integrated representation of the current at
least.

- Brent